eturowski, despite SATTSO's claim, the TSA has NEVER said that the person viewing the NoS image in the back room is the same gender as the person being scanned. NEVER. They have said that the following measures are in place "to preserve privacy":
1) the person viewing the image is in a remote location and cannot directly see the person being scanned;
2) the face is blurred (note they have never said that the genital region is blurred - of course they can see enough of the person's image to identify gender!);
3) the images can't (won't/shouldn't/we-hope-they-won't) be stored;
4) no cameras allowed in viewing room.

This list would have been the perfect place to say "the person viewing the image is the same gender" but they never do.

TSA are relying on people making assumptions and extrapolating from the same-gender patdown.

Also, think of the logistics. One scanner is used for both men and women passengers. You'd have to have two smurfs in the back room, switching back and forth depending on the gender of the passenger; male smurf would have to leave the room or avert his eyes while a female passenger was being scanned. Just not going to happen.

The UK NoS procedure (where fewer passengers are scanned, and where opting out is not allowed) said that passengers could request that someone of the same gender view the image. Again, imagine how that happens in real life. Screener says "you've been randomly selected to be scanned", female passenger says "I request a female screener view the image", screener makes request into radio then tells passenger, "okay, go ahead." How would the passenger even know who was looking at the scan? Why would the screeners bother to change?